I. Field of the Invention
The catalyst of this invention may be utilized, interalia, in processes for preparing unsaturated alcohols. More particularly, such catalysts may be utilized to prepare alpha, beta-ethylenically unsaturated alcohols from alpha, beta-ethylencially unsaturated aldehydes by direct hydrogenation.
II. Summary of the Prior Art
The preparation of alpha, beta-ethylenically unsaturated alcohols by the hydrogen reduction of alpha, beta-ethylenically unsaturated carbonylic compounds may be represented by the following equation: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be hydrogen or lower alkyl. Such, or similar processes utilizing catalysts are described, for example, in U.S. Pat. No. 2,763,696 (Finch et al), U.S. Pat. No. 2,767,221 (Ballard et al), U.S. Pat. No. 3,655,777 (Rylander et al), and Broadbent et al, J. Org. Chem. 24, 1844 -- 54 (1959).
Processes utilizing catalysts for the vapor phase hydrogenation of alpha, beta-ethylenically unsaturated carbonylic compounds to alpha, beta-ethylencially unsaturated alcohols are disclosed in U.S. Pat. No. 2,763,696 and U.S. Pat. No. 2,767,221 but such catalysts suffer from the disadvantages of low selectivity as well as the need for relatively high reaction temperatures and pressures. Further, those catalysts which are utilized to carry out the hydrogenation of alpha-beta unsaturated aldehydes in a liquid phase may result in undesirable polymerization reactions.
The search has continued for improved catalysts particularly suited for preparing alpha, beta-ethylenically unsaturated alcohols by the vapor phase hydrogenation of alpha, beta-ethylenically unsaturated aldehydes. This invention was made as a result of that search although such compositions may also be used to catalyze other reactions.